As disclosed in Unexamined Japanese Patent Application KOKAI Publication No. 2005-279891, a portable abrasive tool such as a sander and polisher works with the pad supporting an abrasive sheet such as a sanding paper being driven by a motor. Generally, the motor used in a portable abrasive tool is composed of a rotor consisting of a coil wound around a columnar iron core extending in the axial direction of the output shaft of the motor and a cylindrical stator enclosing the rotor. Then, the motor is accommodated in the housing of a portable abrasive tool that is held by the user.
In a portable abrasive tool having the motor as described above, the rotor and stator are elongated in the axial direction of the output axis of the motor. Therefore, the housing of a portable abrasive tool is governed by the motor in shape and it is difficult to produce a portable abrasive tool compact in the axial direction of the motor output shaft. As the dimension in the axial direction of the motor output shaft is increased, the abrasive surface and the gravity center of the abrasive tool are more separated. Then, a problem is that the abrasive surface is easily tilted during abrasive operation, making the abrasive operation difficult to handle.